[GHC] #15576: Hadrian puts its build tree in the wrong place

[GHC]

#15576: Hadrian puts its build tree in the wrong place
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        Reporter:  simonpj           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by simonpj):

 I double-checked.

 * I removed `/home/simonpj/ghc/_build` entirely
 * I removed `/playpen/ghc/_build` entirely
 * I did `cd /playpen/ghc`
 * And then `hadrian/build.sh -c -j20 --flavour=quick`

 Result:

 * a `_build` directory immediately appeared in `/home/simonpj/ghc`,
 populated with `generated`, `hadrian`, `stage0`, `stage1`.
 * The `hadrian/` directory contains `.shake.database`.
 * No `_build` directory appeared in `/playpen/ghc`

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15576#comment:4>
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